Drill for drilling rails and track rigs for railroad applications

Abstract: Drill for drilling rails and track rigs, in railroad applications, including a body (3) which supports a motor (6) driving a drilling tool (11) through a reduction unit (12). Elements (20-25) are provided for the translatory motion of the drilling tool with respect to the body. There are also elements (50,52,53) for removably fixing the body with respect to the element (51) to be drilled.

Description: The present invention relates to a drill for drilling rails and track rigs for railroad applications. It is known that drilling devices adapted specifically for use on track rails are currently commercially available. Such devices, which have particular constructive characteristics, have rather considerable dimensions and weights which often cause great difficulties in use. Such devices generally have an electric motor or an internal-combustion engine which is mounted coaxially with the drill or milling cutter and which advances rigidly with the drill. This type of structure, with the motor mounted so that it is axially aligned with the drilling tool and lies along its extension, entails a considerable longitudinal dimension which often is not compatible with the space available in some points of the track, such as rail switches and the like. To the aforesaid it should be added the fact that in versions with an internal-combustion engine the exhaust of the combustion gases of the engine is often directed towards the operator, who consequently finds himself working in a toxic environment. Such devices, as previously mentioned, are generally very heavy, and therefore movement is difficult; furthermore, in most cases they cannot be used by a single operator. Conventional devices are generally predisposed only to execute holes horizontally, i.e. a hole whose axis is perpendicular to the stem of the rail, whereas in railroad applications it is often necessary to execute holes vertically, for example in the slabs supporting the boxes for the electrical actuation of rail switches; in this case it is necessary to use different devices, as it is not possible to modify the conventional drill adapted only to make horizontal holes. A drill having the features set forth in the preamble of claim 1 is known from the prior document US-A-1 671 575. A principal aim of the present invention is to eliminate the above mentioned drawbacks by providing a drill for drilling rails and track rigs for railroad applications which is structured so as to allow to work both horizontally and vertically and in all the positions occurring in the field of railroads. Within the scope of the above mentioned aim, a particular object of the invention is to provide a drill which is very compact and handy and can consequently be used even in narrow spaces, such as are typically available at rail switches. Another object of the present invention is to provide a drill which has a considerably reduced weight with respect to conventional devices, so that it can be used in all the circumstances which occur in railroad systems and can be easily carried even by a single operator. Another object of the present invention is to provide a drill which is particularly versatile and practical in use and furthermore gives the greatest assurances of reliability and safety. A further object of the present invention is to provide a drill for drilling rails and track rigs, in railroad applications, which can be easily obtained starting from commonly commercially available elements and materials and is advantageous from a purely economical point of view. With this aim, the objects mentioned and others which will become apparent hereinafter in view, there is provided a drill for drilling rails and track rigs, in railroad applications, according to the invention and having the features of claim 1. Further inventive features are set forth in the dependent claims. The characteristics and advantages of the drill for drilling rails and track rigs in railroad applications according to the present invention will become apparent from the following detailed description of preferred but not exclusive embodiment thereof, illustrated only by way of non-limitative example in the accompanying drawings, wherein: figure 1 is a schematic elevation view of a drill according to the invention, driven by an electric motor; figure 2 is an elevation view of a drill according to the invention driven by an internal-combustion engine; figure 3 is a sectional view of the drill with the electric motor applied to the web of the rail; figure 4 is a sectional view of the drill with the internal-combustion engine applied to the web of the rail; figure 5 is a schematic view of the drill applied to the flange of the rail and positioned outside its profile; figures 6 and 7 are sectional views, taken along two perpendicular planes, of a jig for the positioning and fixing of the drill to drill the slabs that support the boxes for the electric actuation of rail switches; figure 8 is a sectional view of the detail of the connection of the actuation lever of the means for the translatory motion of the tool shown in released position; figure 9 illustrates the connection of the actuation lever of the means for translatory motion in locked position; figure 10 is a sectional view, taken along the plane X-X of figure 9. With reference to the above figures, the drill for drilling rails and track rigs, in railroad applications, according to the invention, which is generally designated by the reference numeral 1 for the electric-motor version and by the reference numeral 2 for the internal-combustion engine version, comprises a body 3 which is substantially L-shaped and is advantageously made of aluminum alloys. The body 3 has a first wing 4 which delimits, at its free end, a flange 5 for the coupling of an electric motor 6 or a different flange 7 for the coupling of an internal-combustion engine designated by the reference numeral 8. The motor 6 and the engine 8 are located above the second wing 9 of the body 3, so that the drill assembly assumes a substantially U-shaped configuration in which the output shaft, designated by 10 both for the electric motor and for the internal-combustion engine, is arranged parallel to, and spaced from, the tool's working axis. The actuation motor or engine is connected to the tool, generally designated by the reference numeral 11, by means of the interposition of a reduction unit 12 which is advantageously constituted by a train of gears which are directly supported by the body 3. The version driven by an internal-combustion engine is characterized in that the shaft of said engine is connected to the reduction unit by means of an elastic coupling 15; the casing of the engine furthermore does not rest directly on the body of the drill but is coupled to it advantageously by interposing four vibration-damping bushes 16. These constructive solutions avoid the transmission of unwanted mechanical stresses from the engine to the body of the tool, such as for example the vibrations produced by the engine itself during operation. An important particularity of the invention resides in the fact that there are means for the translatory motion of the tool with respect to the body, so that during the advancement of the tool, both the body and the motor or engine remain in a fixed position and therefore only very small masses move. Said translatory motion means comprise a sleeve 20 which is internally grooved and is connected to the last gear of the reduction unit chain so that it is rotated by actuating the motor 6 or engine 8. Inside the grooved sleeve 20 there is a grooved hollow shaft 21 which is rotationally coupled thereto and can slide with respect to it. The shaft 21 is rotatably supported by a slider 22 which has, on its surface, a rack portion 24 meshing with a gear 25 connected to a feed lever 26. The actuation of the lever 26 causes the translatory motion of the slider 22 and of the grooved shaft which is supported by it and rotated by the grooved sleeve 20. The grooved shaft 21 is provided, at its working end, with a spindle 27 for clamping the tool, which can be constituted by a milling cutter or by a helical drill provided with a cooling channel which is connected in a per se known manner to a refrigeration system controlled by a ball 30. Another important aspect is the fact that inside the grooved shaft 21 there is a fixed abutment rod 40 which is connected to the body at its inner end and has its free end arranged proximate to the ball 30. The abutment rod 40 allows to eject the drilling scrap; when the drilling tool is constituted by a milling cutter, ejection is performed automatically during the backoff step, since as the tool backs off the carrot is expelled automatically. At the free end of the second wing 9 of the body 3 it is possible to fix various jigs for fixing the body 3 at the element to be drilled. With reference for example to figure 3, there is a jig, designated by the reference numeral 50, which engages the web 51 of the rail; a bridge-like lever system 52 which passes above the rail then fixes an abutment 53 on the other edge of the web. When it is necessary to mount the drill outside the profile, there is a system, designated by the reference numeral 60, for locking to the flange of the rail; by engaging below said foot, said system allows to arrange the drill so that the body 3 lies on a horizontal plane, so that it is possible to keep the drill connected to the rails even when trains pass. To perform vertical drillings, figures 6 and 7 illustrate a jig 70 equipped with a triangular bracket 71 for fixing to the profiles 72 which are located at the slabs that support the boxes for the electric actuation of rail switches. Another characteristic of the invention is the fact that the actuation lever 26 of the translatory motion means is equipped with initial stroke positioning means which are more clearly illustrated in figures 8 to 10. Said means, generally designated by the reference numeral 80, comprise a cap 81 fixed to the end of the actuation lever 26 and rotatably coupled around a tang 82 which is axially aligned with, and rigidly coupled to, the shaft 83 of the gear 25. The cap 81 and the tang 82 are mutually coupled by means of a polygonal bar portion 85 which is accommodated in a polygonal seat 86 formed by the tang and can engage in a polygonal cavity 87 formed by the cap in order to rigidly rotationally couple them. A stem 89 is connected to the polygonal bar 85 and ends with a button 90 protruding from the cap; a pusher spring 91 furthermore acts on the polygonal bar 85 and tends to move it into engagement with the cavity 87. To perform angular positioning it is enough to apply pressure on the button 90, disengaging the polygonal bar from the polygonal cavity 87 and thus performing the required positioning of the lever 26, which is set by releasing the button 90, consequently causing the polygonal bar 85 to engage the polygonal cavity 87; this engagement rigidly rotationally couples the cap 81 to the tang 82. For the sake of completeness, it should also be noted that a pin 95 is supported by the cap 81 and engages an annular groove 96 formed by the tang to prevent the axial disengagement of the cap with respect to the tang. Therefore, during practical operation a drill is provided which is particularly compact in size by virtue of the fact that the motor or engine is arranged so that one of its axes is parallel to, and spaced from, the axis of the tool, so that the entire drill has overall dimensions that are considerably smaller than those of the known art. Furthermore, since the moving masses are considerably limited, it is possible to use an aluminum alloy structure for the body which consequently has a very reduced weight. The versatility of the drill is furthermore completed by the fact that the adopted configuration allows to apply to the body a plurality of jigs for coupling to the element to be drilled, so that said drill can be used for both horizontal and vertical drillings. Furthermore, the presence of the means for the initial positioning of the lever allows to set the actuation lever always in the optimum position for the operator. The invention thus conceived is susceptible to numerous modifications and variations within the scope of the appended claims. All the details may furthermore be replaced with other technically equivalent elements. In practice, the materials employed, as well as the contingent shapes and dimensions, may be any according to the requirements. Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the scope of each element identified by way of example by such reference signs.

Claims: Drill (1;2) for drilling rails and track rigs, in railroad applications, comprising: a body (3) which supports a motor (6;8) that drives a drilling tool (11) through a reduction unit (12), the output shaft (10) of said motor being substantially parallel to and spaced from the axis of said tool (11); means (20-26) for the translatory motion of said drilling tool with respect to said body; and means (50;60;70) for removably fixing said body with respect to an element (51;72) to be drilled, characterized in that said body (3) is substantially L-shaped, with a first wing (4) that forms a flange (5;7) for coupling to said motor, and a second wing (9) for accommodating said tool, the second wing (9) being substantially perpendicular to said first wing, and said motor being coupled at said flange (5; 7) in a position located above said second wing (9) with said output shaft (10) being superimposed on the axis of said tool (11) so that the drill assembly assumes a substantially U-shaped configuration. Claim according to claim 1, characterized in that said body (3) is made of aluminium alloys. Drill according to one or more of the preceding claims, characterized in that in a version driven by an internal-combustion engine (8) said output shaft (10) is connected to said reduction unit (12) by means of an elastic coupling (15) and said engine is connected to said body by means of the interposition of vibration-damping bushes (16). Drill according to one or more of the preceding claims, characterized in that said means for removably fixing said body with respect to the element to be drilled are constituted by interchangeable jigs (50;60;70) which can be removably coupled to the free end of said second wing of said body. Drill according to claim 4, characterized in that said jigs comprise a jig (50) for engaging a rail web (51), a jig (60) for locking to a rail flange and a jig (70) for fixing to profiles (72) located at slabs supporting boxes for electric actuation of rail switches. Drill according to one or more of the preceding claims, characterized in that said translatory motion means comprise a sleeve (20) which is internally grooved, kinematically connected to said reduction unit (12), and slidingly coupleable to a hollow grooved shaft (21) which forms the supporting spindle for said tool (11). Drill according to claim 6, characterized in that it comprises a slider (22) which is slidingly coupled to said body and rotatably supports said grooved shaft (21), said slider having, on its surface, a rack-like segment (24) with which a gear meshes (25), said gear being connected to an actuation lever (26). Drill according to one or more of the preceding claims, characterized in that it comprises a fixed abutment rod (40) which is supported by said body and extends inside said grooved shaft, the free end of said fixed abutment rod acting as a device for expelling the drilling scrap following the return of said slider to its initial position. Drill according to claim 8, characterized in that said rod (40) has said free end thereof in proximity of a ball (30) which controls a refrigeration system connected to a cooling channel of the drilling tool (11). Drill according to claim 7, characterized in that it comprises means (80) for the initial positioning of said actuation lever. Drill according to claim 10, characterized in that said initial positioning means comprise a cap (81) which is fixed to the end of said actuation lever (26) and is rotatably coupleable around a tang (82) which is axially aligned with, and rigidly coupled to, the driving shaft (83) of said gear (25) which meshes with said slider (22), a polygonal bar segment (85) being furthermore provided which is accommodated in a polygonal seat (86) formed by said tang and is removably engageable in a polygonal cavity (87) formed by said cap in order to rigidly rotationally couple said cap to said tang, a stem (89) being connected to said bar, said stem ending with a button (90) that protrudes from said cap, said polygonal bar segment being removably disengageable from said polygonal cavity for the initial positioning of said actuation lever.

Inventors: PERONI ENNIO, PERONI, ENNIO
Applicants: CEMBRE SPA, CEMBRE S.P.A.
Application year: 1994
Main classification: E01B31
IPC codes: E01B31, B23B41, B23B45